In the past, as this type of substrate case cleaning apparatus, for example, the one which is described in PLT 1 (Japanese Patent Publication No. 2005-109523A) was known. As shown in FIG. 22, this substrate case cleaning apparatus Sa cleans a substrate case C, which comprises a base Cb and a shell Cs which covers this base Cb and which holds a substrate (not shown) at its inside, in the state with no substrate. The substrate case cleaning apparatus Sa is provided with a booth 200 which forms a clean space. Inside this booth 200, a cleaning tank 201 is provided which holds and cleans the parts of the base Cb and shell Cs in a separated state. The cleaning tank 201 is provided with a tank body 202 which has an opening which opens to above and a lid 203 which opens and closes the opening of the tank body 202. At the outside of the booth 200, a setting table 204 which carries the substrate case C is provided. An arm robot 205 grips the substrate case C which is carried on the setting table 204 by a gripping hand 207 and conveys it to a support table 206 which is provided at the inside of the booth 200. Further, the arm robot 205 grips the shell Cs of the substrate case C which is supported at the support table 206 by the gripping hand 207 and conveys it to the inside of the tank body 202 of the cleaning tank 201 and conveys the base Cb of the substrate case C to the lid 203 of the cleaning rank 201 to set it there. After that, the lid 203 is closed. In that state, the shell Cs and base Cb are cleaned inside of the tank body 202. When the cleaning ends, the lid 203 of the cleaning tank 201 is opened, and the arm robot 205 successively conveys the base Cb and shell Cs of the substrate case C on the support table 206 where they are assembled into the substrate case C. Further, again, the arm robot 205 conveys the substrate case C from the support table 206 to the setting table 204 outside of the booth 200.